Which of the following numbers is a factor of 184? ${2,6,7,10,13}$
Solution: By definition, a factor of a number will divide evenly into that number. We can start by dividing $184$ by each of our answer choices. $184 \div 2 = 92$ $184 \div 6 = 30\text{ R }4$ $184 \div 7 = 26\text{ R }2$ $184 \div 10 = 18\text{ R }4$ $184 \div 13 = 14\text{ R }2$ The only answer choice that divides into $184$ with no remainder is $2$ $ 92$ $2$ $184$ We can check our answer by looking at the prime factorization of both numbers. Notice that the prime factors of $2$ are contained within the prime factors of $184$ $184 = 2\times2\times2\times23 2 = 2$ Therefore the only factor of $184$ out of our choices is $2$. We can say that $184$ is divisible by $2$.